This study is a Phase I, single-dose, open-label trial designed to evaluate the pharmacokinetics and safety of a single oral dose of 25 mg VC005 tablets in participants with mild and moderate hepatic impairment compared to participants with normal hepatic function.

Inclusion Criteria:

1. Voluntarily sign the informed consent form prior to the trial, fully understand the trial content, procedures, and possible adverse reactions, and be able to complete the study in accordance with the protocol requirements;
2. Participants (including their partners) are willing to have no pregnancy plan from screening until 3 months after the last study drug administration and voluntarily take effective contraceptive measures; and have no plans to donate sperm or eggs;
3. Male and female participants aged 18 to 79 years (inclusive);
4. Male participants weighing no less than 50.0 kg, female participants weighing no less than 45.0 kg. Body mass index (BMI) between 18 and 32 kg/m² (inclusive).

Exclusion Criteria:

1. History of allergies, including to drugs, food, dust mites, etc., known allergy to the study drug or any of its components;
2. History of drug abuse, drug addiction and/or alcohol abuse (consumption of 14 units of alcohol per week: 1 unit = 285 mL beer, or 25 mL spirits, or 100 mL wine); positive results in drug abuse screening and alcohol screening;
3. Blood donation or significant blood loss (> 400 mL) within 3 months prior to screening; or plan to donate blood during the trial; or use of albumin within 14 days before the first dose of the study drug;
4. Average daily smoking of more than 5 cigarettes within 3 months prior to screening; or inability to stop using any tobacco products during the trial;
5. History of recurrent herpes zoster, disseminated herpes zoster, or disseminated herpes simplex;
6. Known active bacterial, viral, fungal, parasitic infection or other infection, or any infectious event requiring antibiotic treatment or hospitalization (within 4 weeks prior to screening), or any acute infection within 2 weeks of baseline;
7. History of dysphagia or, within 6 months prior to screening, any gastrointestinal conditions affecting drug absorption or excretion (e.g., reflux esophagitis, peptic ulcer, chronic diarrhea, chronic constipation), history of renal disease (confirmed renal disease regardless of cure; if only laboratory abnormalities such as elevated creatinine, hematuria, etc., to be assessed by the investigator), and history of surgery (e.g., gastrointestinal surgery and other major surgeries).